
package filter;

import java.io.IOException;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpServletResponseWrapper;
import managedbean.Controller;


@WebFilter(filterName = "AuthenticationFilter", urlPatterns={"/innersystem/*"})
public class AuthenticationFilter implements Filter {
    
    private static final boolean debug = false;
    
    private FilterConfig filterConfig = null;
    
    public AuthenticationFilter() {
    }    
    
    private void doBeforeProcessing(RequestWrapper request, ResponseWrapper response)
            throws IOException, ServletException {
        if (debug) {
            log("AuthenticationFilter:DoBeforeProcessing");
        }       
    }    
    
    private void doAfterProcessing(RequestWrapper request, ResponseWrapper response)
            throws IOException, ServletException {
        if (debug) {
            log("AuthenticationFilter:DoAfterProcessing");
        }        
    }

    public void doFilter(ServletRequest request, ServletResponse response,
            FilterChain chain)
            throws IOException, ServletException {
        
        if (debug) {
            log("AuthenticationFilter:doFilter()");
        }

        RequestWrapper wrappedRequest = new RequestWrapper((HttpServletRequest) request);
        ResponseWrapper wrappedResponse = new ResponseWrapper((HttpServletResponse) response);
        
        doBeforeProcessing(wrappedRequest, wrappedResponse);
        
        Throwable problem = null;
        
        try {
            HttpServletRequest req = (HttpServletRequest) request;
            HttpServletResponse res = (HttpServletResponse) response;
            Controller controller = (Controller) req.getSession().getAttribute("controller");
            if (controller == null || !controller.isLoggedIn()){
                String port = ":8080";
                String url = "http://" + req.getServerName() + port + req.getContextPath() + "/index.xhtml";
                res.sendRedirect(url);
            }
            else{
                chain.doFilter(wrappedRequest, wrappedResponse);
            }
        } catch (Throwable t) {
            problem = t;
            t.printStackTrace();
        }
        
        doAfterProcessing(wrappedRequest, wrappedResponse);

        if (problem != null) {
            if (problem instanceof ServletException) {
                throw (ServletException) problem;
            }
            if (problem instanceof IOException) {
                throw (IOException) problem;
            }
            sendProcessingError(problem, response);
        }
    }

    public FilterConfig getFilterConfig() {
        return (this.filterConfig);
    }

    public void setFilterConfig(FilterConfig filterConfig) {
        this.filterConfig = filterConfig;
    }

    public void destroy() {        
    }

    public void init(FilterConfig filterConfig) {        
        this.filterConfig = filterConfig;
        if (filterConfig != null) {
            if (debug) {                
                log("AuthenticationFilter: Initializing filter");
            }
        }
    }

    @Override
    public String toString() {
        if (filterConfig == null) {
            return ("AuthenticationFilter()");
        }
        StringBuffer sb = new StringBuffer("AuthenticationFilter(");
        sb.append(filterConfig);
        sb.append(")");
        return (sb.toString());
        
    }
    
    private void sendProcessingError(Throwable t, ServletResponse response) {
        String stackTrace = getStackTrace(t);        
        
        if (stackTrace != null && !stackTrace.equals("")) {
            try {
                response.setContentType("text/html");
                PrintStream ps = new PrintStream(response.getOutputStream());
                PrintWriter pw = new PrintWriter(ps);                
                pw.print("<html>\n<head>\n<title>Error</title>\n</head>\n<body>\n"); //NOI18N

                // PENDING! Localize this for next official release
                pw.print("<h1>The resource did not process correctly</h1>\n<pre>\n");                
                pw.print(stackTrace);                
                pw.print("</pre></body>\n</html>"); //NOI18N
                pw.close();
                ps.close();
                response.getOutputStream().close();
            } catch (Exception ex) {
            }
        } else {
            try {
                PrintStream ps = new PrintStream(response.getOutputStream());
                t.printStackTrace(ps);
                ps.close();
                response.getOutputStream().close();
            } catch (Exception ex) {
            }
        }
    }
    
    public static String getStackTrace(Throwable t) {
        String stackTrace = null;
        try {
            StringWriter sw = new StringWriter();
            PrintWriter pw = new PrintWriter(sw);
            t.printStackTrace(pw);
            pw.close();
            sw.close();
            stackTrace = sw.getBuffer().toString();
        } catch (Exception ex) {
        }
        return stackTrace;
    }
    
    public void log(String msg) {
        filterConfig.getServletContext().log(msg);        
    }

    /**
     * This request wrapper class extends the support class HttpServletRequestWrapper,
     * which implements all the methods in the HttpServletRequest interface, as
     * delegations to the wrapped request. 
     * You only need to override the methods that you need to change.
     * You can get access to the wrapped request using the method getRequest()
     */
    class RequestWrapper extends HttpServletRequestWrapper {
        
        public RequestWrapper(HttpServletRequest request) {
            super(request);
        }
        // You might, for example, wish to add a setParameter() method. To do this
        // you must also override the getParameter, getParameterValues, getParameterMap,
        // and getParameterNames methods.
        protected Hashtable localParams = null;
        
        public void setParameter(String name, String[] values) {
            if (debug) {
                System.out.println("AuthenticationFilter::setParameter(" + name + "=" + values + ")" + " localParams = " + localParams);
            }
            
            if (localParams == null) {
                localParams = new Hashtable();
                // Copy the parameters from the underlying request.
                Map wrappedParams = getRequest().getParameterMap();
                Set keySet = wrappedParams.keySet();
                for (Iterator it = keySet.iterator(); it.hasNext();) {
                    Object key = it.next();
                    Object value = wrappedParams.get(key);
                    localParams.put(key, value);
                }
            }
            localParams.put(name, values);
        }
        
        @Override
        public String getParameter(String name) {
            if (debug) {
                System.out.println("AuthenticationFilter::getParameter(" + name + ") localParams = " + localParams);
            }
            if (localParams == null) {
                return getRequest().getParameter(name);
            }
            Object val = localParams.get(name);
            if (val instanceof String) {
                return (String) val;
            }
            if (val instanceof String[]) {
                String[] values = (String[]) val;
                return values[0];
            }
            return (val == null ? null : val.toString());
        }
        
        @Override
        public String[] getParameterValues(String name) {
            if (debug) {
                System.out.println("AuthenticationFilter::getParameterValues(" + name + ") localParams = " + localParams);
            }
            if (localParams == null) {
                return getRequest().getParameterValues(name);
            }
            return (String[]) localParams.get(name);
        }
        
        @Override
        public Enumeration getParameterNames() {
            if (debug) {
                System.out.println("AuthenticationFilter::getParameterNames() localParams = " + localParams);
            }
            if (localParams == null) {
                return getRequest().getParameterNames();
            }
            return localParams.keys();
        }        
        
        @Override
        public Map getParameterMap() {
            if (debug) {
                System.out.println("AuthenticationFilter::getParameterMap() localParams = " + localParams);
            }
            if (localParams == null) {
                return getRequest().getParameterMap();
            }
            return localParams;
        }
    }

    /**
     * This response wrapper class extends the support class HttpServletResponseWrapper,
     * which implements all the methods in the HttpServletResponse interface, as
     * delegations to the wrapped response. 
     * You only need to override the methods that you need to change.
     * You can get access to the wrapped response using the method getResponse()
     */
    class ResponseWrapper extends HttpServletResponseWrapper {
        
        public ResponseWrapper(HttpServletResponse response) {
            super(response);            
        }
        // You might, for example, wish to know what cookies were set on the response
        // as it went throught the filter chain. Since HttpServletRequest doesn't
        // have a get cookies method, we will need to store them locally as they
        // are being set.
	/*
        protected Vector cookies = null;
        
        // Create a new method that doesn't exist in HttpServletResponse
        public Enumeration getCookies() {
        if (cookies == null)
        cookies = new Vector();
        return cookies.elements();
        }
        
        // Override this method from HttpServletResponse to keep track
        // of cookies locally as well as in the wrapped response.
        public void addCookie (Cookie cookie) {
        if (cookies == null)
        cookies = new Vector();
        cookies.add(cookie);
        ((HttpServletResponse)getResponse()).addCookie(cookie);
        }
         */
    }
}
